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9 bolt trouble ?

WS6

WS6

Stay thirsty my friends
Anyone here have trouble with the 9 bolt we have? I mean typical problems that crop up under abuse?

Reason I ask is that I bought this car with different ratio(3.45) than original and I've always been suspicious of the pinion depth and lash. I could just feel it and sort of hear it. Well, I went to the dealer where I have stuff done that I can't do and my mechanic of choice for these things drove it and confirmed my suspicions. Seems to be getting worse too, but maybe I've got tunnel vision about it now.

So I ordered a rebuild kit from ratech and ordered the heavy duty pinion bushing to replace the the crush sleeve altogether.

Is there something else I should have done while it's apart?:bleed:
 
If you're talking about a "thunk" when putting in Drive....that's normal.

If you're talking about a slight whine at low speed...normal.

Any other noises...probably not normal.
 
It whines but from 25 up through 75 MPH and probaby higher but other noises drown it out. There is also a low speed rythmic noise, much like a an axle bearing or pinion bearing failure.
 
unfortunately it sounds like you diagnosed it correctly. Definately not normal. Let us know if it was the pinion bearing once you've rebuilt.
 
From my research of these axles I gather,much like you mentioned, that there is some noise, especially if the toe is set up that way. But that is a racers trick and not really meant for street driving.

I'm on the fence about this whoile thing because axle rebuilding is not a cheap date and I'd rather spend the money on something else. BUT, used 9 bolts are getting scarce and expensive and they usually need work too.
If I'd tear up the carrier horseing around one day I'd never forgive myself for not solving the problem first.

All that I know is that someone else changed the ring and pinion out and based on what else has been done it could very well have been done incorrectly.
 
I have mine apart right now. the posi usually goes bad , then the cones need to be milled and shimmed to work right again. booth my axel seals were leaking, so i just bought a 9 bolt from my friend that has 19000 miles on it. From what some one told me, the replacement axel bearings and seals sit in a different spot so they will not leak. this was a common problem i was told from gm tech. I was figuring on putting in a 12 bolt soon and keeping the 9 bolt on the side for originality when or if i sell the car. good luck!
 
Well the repeated hard launches during tuning and goofing around have taken thier toll. So much so that I was afraid to drive it another 50 yards. I just watched it being flat bedded away to the garage. I was hoping it would last longer because the shop is so busy they can't tie up a bay for that long. So now it will sit there till it gets fixed. I have the complete rebuild kit, I just hope I didn't take any teeth off the ring or pinion. It was so loud rolling along that it was frightening old ladies and small children.
 
Well? The pinion chunked off 2 teeth. Best guess is the lash was too tight and the pinion bearing was bad.

Question is...I have found a set of 3.27's (original ratio) and a set of new,aftermarket 3.70 ratio.

Which to buy? take into consideration the 9" 3200 stall convertor,non lock up.

Give me some opinions PLEASE!! and quick too!



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Re: 9 bolt trouble ? BUMP!

:poke:anyone?? have a ratio choice opinion???
 
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Well I got my answer and it was what I was suspecting. 3.27 is the gear for these cars.

I called John Pearcy and we spoke about it at length, he told me that the turbo cars need the load of the lower numerical ratios. If not I'd need to run 28" tall tires.
While we were talking he asked about what turbo and convertor I was running and he told me the Art Carr 9" 3200 is way too much convertor for what I'm using it for. Which is primarily street and occasional race. He suggested a 2800 stall with a lock up convertor as this is proven combination for high 11 cars with 49/44 turbos.

Thoughts??

...
 
Yes 3.27, Most drag radials are 26 inches tall. at the end of the 1/4 you will be at about 5500-5700 which is okay, you do not want to shift overdrive , so keep the 3.27. If you have alot of mods and a roller cam... you could get away with a diff. ratio. You should change all the bearings while its apart, carrier, pinion and axel bearings. Good luck!
 
WS6 said:
Well I got my answer and it was what I was suspecting. 3.27 is the gear for these cars.

I called John Pearcy and we spoke about it at length, he told me that the turbo cars need the load of the lower numerical ratios. If not I'd need to run 28" tall tires.
While we were talking he asked about what turbo and convertor I was running and he told me the Art Carr 9" 3200 is way too much convertor for what I'm using it for. Which is primarily street and occasional race. He suggested a 2800 stall with a lock up convertor as this is proven combination for high 11 cars with 49/44 turbos.

Thoughts??

...
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That's exactly what I'm doing when my trans comes out. Non Lock up 2800. Durable, Jack Cotton also reccomends that combo. That turbo performs well with the stock convertor, but will probably perform even better with a 2800.
Have you done searches for new rear end parts? I have also heard that they re getting hard to find.
 
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sverble said:
Have you done searches for new rear end parts? I have also heard that they re getting hard to find.
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I bought the "complete" axle rebuild kit and pinion spacer to replace the crush sleeve. Apparently this is one of weak links of the BW rear end.
http://ratech.stores.yahoo.net/79bogmax.html

Parts are somewhat hard to find, but ratech had all the small parts and for what I thought was a reasonable price( $131). Ring and pinions are hard to find in any ratio but 3.70 new. I did find NOS R&P's in just about all ratios from 2.77 up through 3.45 but they are $550 a set.

I bought a used 3.27 off e-bay($90). I also found axles,alum preload covers and posi units used on e-bay. So parts are out there to be had, just requires some time.

I think that 5 years ago the 9 bolt was expensive to rebuild, from old threads I've found at TGO, but prices seem to have come down quite a bit. Now labor is an entirely different animal. I'm getting a discount at $60 per hour and I bet I'll be buying 6-8 hours of rack time for this.Or more....:jaw:
 
Update: Heads up. That complete install kit doesn't have the axle bearings or seals. But autozone will have them tomorrow.

The tech called me to give me the cause of the pinion failure and it wasn't that the lash was too tight. But it was a similar reason. Can you guess? It was a human error.

When I get all the damaged pieces I'll post pictures of the carnage and the reason for the carnage.


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That price has come down too, as with "most" of the other BW parts.
http://cgi.ebay.com/ebaymotors/Chev...9784135QQcmdZViewItem?_trksid=p3756.m20.l1116

But there is virtually no NOS ring and pinion stuff unless you want to spend over $590 http://www.ringpinion.com/PartsList.aspx?SearchMode=Make&MakeID=17&MakeName=Buick+%2f+Olds+%2f+Pontiac&ModelID=308&ModelName=Firebird+Trans+Am&Side=Rear&DiffID=41&DiffName=GM+7.75&CatID=10&CatName=Rings+%26+Pinions&CatType=Sub-Differential

I'm still waiting on one axle bearing and both axle seals, but hopefully It'll be done by early next week.


:coffee:

What it ended up being the culprit of this failure was a plastic cap off a gear lube fill bottle. That's right, that little cone cap must have still been on the end of an open bottle when they were topping it off and they must have squeezed it out in to the center section. Well it got chewed up and some if it wound up inside the pinion bearing and the big piece must have found it's way in the mesh of the R&P. Just enough mass to put untold pressure on the lash. Could have knocked me over with a feather when I saw it. He told me he has seen it before though, Guys put a little extension hose on the bottle to fill it up and they squeeze of the the hose off into the center section and figure what the hell, it's only plastic. But it does take up space,especially in the mesh or bearing themselves.

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Good luck with that. I have put two sets of used ring and pinions in, and they make noise on decel, no matter what I do. I have a TA 49 with a precision 3200 stall, and am completely happy with it. I ran an [email protected] mph.
 
I know, used gears=big trouble...but other than 3.70 ratio there are no 3.27,3.45 available new. They list them for sale but it's all out of stock.
 
I don't know if you beleive in God, Karma, or whatever. This is his way of telling you it is time to make a full upgrade to a bulletproof Strange 60 rearend, Lol!!!!!

A 3.70 is a pretty big difference. I wonder if you could find an entire used rear that was worth buying? If you could find one that might be a better choice that using a used ring and pinion in your housing.

If I didn't have my motor project going I'd consider selling you my rear diff and upgrading my own. I'd be devorced if I tried that now. My wife has been REALLY cool about the project so far but I am sure there must be a limit.

Good luck!

Eric
 
1 QUIK6 said:
I don't know if you beleive in God, Karma, or whatever. This is his way of telling you it is time to make a full upgrade to a bulletproof Strange 60 rearend, Lol!!!!!
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Maybe, but with labor and parts hopefully I'll be out in under $750. What's that, 30% of a Moser or Strange axle? It's just not in the cards. Besides, if GOD wanted me to spend that much I'd have hit the lottery or something. I think this was his way of telling me to "look before you leap" when you buy a modified TTA.

A 3.70 is a pretty big difference. I wonder if you could find an entire used rear that was worth buying? If you could find one that might be a better choice that using a used ring and pinion in your housing.
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3.70 is waaayy to much gear for a turbo (John Pearcy quote) I wouldn't buy a used 9 bolt rear end, I already have one:o. It did cross my mind, and I did look around but they seem to be bringing $350-500 used and some of them look like they were at the bottom of the ocean. I figured I was just buying a grenade that may or may not have the pin pulled.

If I didn't have my motor project going I'd consider selling you my rear diff and upgrading my own. I'd be devorced if I tried that now. My wife has been REALLY cool about the project so far but I am sure there must be a limit.
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I appreciate the consideration but like you my wife is rapidly losing her sense of humor about this car. I need to get some street time in to prove it's not just a money pit and that it can actually move people around.
:chat:
 
Here's the carnage, with picture of the culprit. Yep, that little plastic cap off the top of a gear lube bottle found it's way into the pinion bearings and probably got sucked up into the ring and pinion gear clash too.
Anyway, it's back on the road with an original 3.27 and what a difference it made. It's never been this quite going down the road since I've owned it. Despite the bearing noise and other obvious noises that it made, the overall cabin noise is way down to just engine noise.
And for the better or worse? it has certainly changed the way it comes off of a dig. It's a little slower so I'll have change the way I launch it. Before it seemed I really didn't have to build any boost to get pull hard off the start and it seems to build boost a little slower, but I've got a lot of tuning left to do.

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pinion005.jpg

pinion003.jpg

pinion002.jpg

pinion001.jpg

pinion007.jpg
 
Glad it's up and running!, After I did my rear I was amazed at how quite the cabin was. I can actually hear the radio on a low setting!:thumbup:
 
WS6 said:
Update: Heads up. That complete install kit doesn't have the axle bearings or seals. But autozone will have them tomorrow.

The tech called me to give me the cause of the pinion failure and it wasn't that the lash was too tight. But it was a similar reason. Can you guess? It was a human error.

When I get all the damaged pieces I'll post pictures of the carnage and the reason for the carnage.


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Do you have the part numbers to order from Autzone (bearings and seals), just thought I get the parts in for any future needs :-)

How hard was the rebuild?
 
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